• Scalability
https://store.theartofservice.com/the-scalability-toolkit.html
Border Gateway Protocol Internal BGP scalability
1 An autonomous system with internal BGP (iBGP) must have all of its iBGP peers
connect to each other in a full mesh (where everyone speaks to everyone directly). This full-mesh configuration requires that each router maintain a session to every other router. In large networks, this number of sessions may degrade performance of
routers, due to either a lack of memory, or too much CPU process requirements.
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Border Gateway Protocol Internal BGP scalability
1 Route reflectors and confederations both reduce the number of iBGP
peers to each router and thus reduce processing overhead. Route
reflectors are a pure performance-enhancing technique, while
confederations also can be used to implement more fine-grained policy.
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Border Gateway Protocol Internal BGP scalability
1 Route reflectors reduce the number of connections required in an AS. A
single router (or two for redundancy) can be made a route reflector: other
routers in the AS need only be configured as peers to them.
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Border Gateway Protocol Internal BGP scalability
1 Confederations are sets of autonomous systems. In common
practice, only one of the confederation AS numbers is seen by
the Internet as a whole. Confederations are used in very large
networks where a large AS can be configured to encompass smaller more manageable internal ASs.
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Border Gateway Protocol Internal BGP scalability
1 Confederations can be used in conjunction with route reflectors.
Both confederations and route reflectors can be subject to
persistent oscillation unless specific design rules, affecting both BGP and
the interior routing protocol, are followed.
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Border Gateway Protocol Internal BGP scalability
1 However, these alternatives can introduce problems of their own, including the following:
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Border Gateway Protocol Internal BGP scalability
1 route oscillation
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Border Gateway Protocol Internal BGP scalability
1 Additionally, route reflectors and BGP confederations were not designed to
ease BGP router configuration. Nevertheless, these are common
tools for experienced BGP network architects. These tools may be combined, for example, as a hierarchy of route reflectors.
https://store.theartofservice.com/the-scalability-toolkit.html
Scalability
1 An analogous meaning is implied when the word is used in an
economic context, where scalability of a company implies that the
underlying business model offers the potential for economic growth within
the company.
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Scalability
1 Scalability, as a property of systems, is generally difficult to define and in any
particular case it is necessary to define the specific requirements for scalability on those dimensions that are deemed important. It is
a highly significant issue in electronics systems, databases, routers, and
networking. A system whose performance improves after adding hardware,
proportionally to the capacity added, is said to be a scalable system.
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Scalability
1 Scalability refers to the ability of a site to increase in size as demand warrants.
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Scalability
1 The concept of scalability is desirable in technology as well as business settings. The base concept is consistent – the ability for a business or technology to accept increased volume without impacting the contribution margin (= revenue − variable costs). For example, a given piece of equipment may
have capacity from 1–1000 users, and beyond 1000 users, additional equipment is needed
or performance will decline (variable costs will increase and reduce contribution margin).
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Scalability Measures
1 Scalability can be measured in various dimensions, such as:
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Scalability Measures
1 Administrative scalability: The ability for an increasing number of
organizations or users to easily share a single distributed system.
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Scalability Measures
1 Functional scalability: The ability to enhance the system by adding new
functionality at minimal effort.
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Scalability Measures
1 Geographic scalability: The ability to maintain performance, usefulness, or
usability regardless of expansion from concentration in a local area to
a more distributed geographic pattern.
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Scalability Measures
1 Load scalability: The ability for a distributed system to easily expand
and contract its resource pool to accommodate heavier or lighter
loads or number of inputs. Alternatively, the ease with which a
system or component can be modified, added, or removed, to
accommodate changing load.
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Scalability Examples
1 A routing protocol is considered scalable with respect to network size,
if the size of the necessary routing table on each node grows as O(log N), where N is the number of nodes
in the network.
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Scalability Examples
1 A scalable online transaction processing system or database
management system is one that can be upgraded to process more transactions by adding new
processors, devices and storage, and which can be upgraded easily and transparently without shutting it
down.
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Scalability Examples
1 Some early peer-to-peer (P2P)
implementations of Gnutella had scaling
issueshttps://store.theartofservice.com/the-scalability-toolkit.html
Scalability Examples
1 The distributed nature of the Domain Name System allows it to work
efficiently even when all hosts on the worldwide Internet are served, so it is
said to "scale well".
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Scalability Horizontal and vertical scaling
1 Methods of adding more resources for a particular application fall into
two broad categories: horizontal and vertical scaling.
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Scalability Horizontal and vertical scaling
1 To scale horizontally (or scale out) means to add more nodes to a system, such as adding a new
computer to a distributed software application
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Scalability Horizontal and vertical scaling
1 To scale vertically (or scale up) means to add resources to a single
node in a system, typically involving the addition of CPUs or memory to a
single computer
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Scalability Horizontal and vertical scaling
1 There are tradeoffs between the two models
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Scalability Database scalability
1 A number of different approaches enable databases to grow to very large size while
supporting an ever-increasing rate of transactions per second. Not to be
discounted, of course, is the rapid pace of hardware advances in both the speed and
capacity of mass storage devices, as well as similar advances in CPU and networking
speed. Beyond that, a variety of architectures are employed in the implementation of very
large-scale databases.
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Scalability Database scalability
1 One technique supported by most of the major database management
system (DBMS) products is the partitioning of large tables, based on
ranges of values in a key field
https://store.theartofservice.com/the-scalability-toolkit.html
Scalability Database scalability
1 Oracle RAC uses a different model to achieve scalability, based on a
"shared-everything" architecture that relies upon high-speed connections
between servers.
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Scalability Database scalability
1 In any case, whether or not adhering to traditional relational concepts,
there appears to be no limit in sight to database scalability.
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Scalability Design for scalability
1 It is often advised to focus system design on hardware scalability rather than on capacity
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Scalability Weak versus strong scaling
1 In the context of high performance computing there are two common notions of scalability.
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Scalability Weak versus strong scaling
1 The first is strong scaling, which is defined as how the solution time
varies with the number of processors for a fixed total problem size.
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Scalability Weak versus strong scaling
1 The second is weak scaling, which is defined as how the solution time
varies with the number of processors for a fixed problem size per
processor.
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Linux Terminal Server Project - Scalability
1 Initially, the MILLE-Xterm project, funded by Canadian public agencies and school
districts in the province of Quebec, created a version of LTSP integrating four
subprojects: a portal (based on uportal), an open-source middleware stack, a CD with
free software for Windows/Mac and, finally, MILLE-Xterm itself. The MILLE-Xterm
project's goal was to provide a scalable infrastructure for massive X-Terminal
deployment.https://store.theartofservice.com/the-scalability-toolkit.html
Linux Terminal Server Project - Scalability
1 MILLE means Modèle d'Infrastructure Logiciel Libre en Éducation (Free Software Infrastructure Model for
Education) and is targeted at educational institutions.
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Linux Terminal Server Project - Scalability
1 As of 2009, MILLE-Xterm was integrated back into the LTSP as
LTSP-cluster, a project specializing in the large scale deployment of LTSP
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Linux Terminal Server Project - Scalability
1 In LTSP-cluster high-availability and high-performance thin-clients are
specified through the optional use of redundant components. Services that
can be load-balanced and made highly available are:
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Linux Terminal Server Project - Scalability
1 LTSP-Cluster can support Linux application servers as well as
Windows application servers and provides a similar level of support,
centralized management, high-availability, and load-balancing
features for both platforms.
https://store.theartofservice.com/the-scalability-toolkit.html
Linux Terminal Server Project - Scalability
1 Also included is support for virtual desktops for remote users using NX
technology. The NX protocol can allow remote Windows and Linux sessions to be accessed from a web browser with
very low bandwidth (40 kbit/s) requirements and tolerance for high-
latency connections. The NX client runs on various Operating Systems including
Linux, Mac, and Windows.
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Storage virtualization - Performance and scalability
1 In some implementations the performance of the physical storage
can actually be improved, mainly due to caching
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Storage virtualization - Performance and scalability
1 Due to the nature of virtualization, the mapping of logical to physical
requires some processing power and lookup tables. Therefore every
implementation will add some small amount of latency.
https://store.theartofservice.com/the-scalability-toolkit.html
Storage virtualization - Performance and scalability
1 In addition to response time concerns, throughput has to be
considered. The bandwidth into and out of the meta-data lookup software directly impacts the available system
bandwidth. In asymmetric implementations, where the meta-
data lookup occurs before the information is read or written,
bandwidth is less of a concern as the meta-data are a tiny fraction of the actual I/O size. In-band, symmetric flow through designs are directly limited by their processing power
and connectivity bandwidths.
https://store.theartofservice.com/the-scalability-toolkit.html
Storage virtualization - Performance and scalability
1 Most implementations provide some form of scale-out model, where the inclusion of additional software or
device instances provides increased scalability and potentially increased
bandwidth. The performance and scalability characteristics are directly
influenced by the chosen implementation.
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Virtual Private LAN Service - Scalability
1 VPLS is typically used to link a large number of sites together. Scalability is therefore an important issue that
needs addressing.
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PRINCE2 - Scalability
1 For this reason every process has a note on scalability
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Extreme programming - Scalability
1 Historically, XP only works on teams of twelve or fewer people. One way to circumvent this limitation is to break up the project into smaller pieces and the team into smaller
groups. It has been claimed that XP has been used successfully on teams
of over a hundred developers. ThoughtWorks has claimed
reasonable success on distributed XP projects with up to sixty people.
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Extreme programming - Scalability
1 In 2004, Industrial Extreme Programming (IXP) was introduced as
an evolution of XP. It is intended to bring the ability to work in large and
distributed teams. It now has 23 practices and flexible values. As it is a new member of the Agile family,
there is not enough data to prove its usability; however it claims to be an
answer to what it sees as XP's imperfections.
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Scalability testing
1 Scalability Testing, part of the battery of non-functional tests, is the testing
of a software application for measuring its capability to scale up or scale out - in terms of any of its non-functional capability - be it the user load supported, the number of transactions, the data volume etc.
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Scalability testing
1 Performance, scalability and reliability are usually considered
together by software quality analysts.
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Scalability testing - Tools
1 Scalability testing tools exist (often leveraging scalable resources
themselves) in order to test load, concurrent connections, transactions,
and throughput of many internet services. Of the available testing
services, those offering API support suggest that environment of continuous deployment also continuously test how recent
changes may impact scalability.https://store.theartofservice.com/the-scalability-toolkit.html
Scalability testing - Tools
1 SandStorm Cloud Edition
https://store.theartofservice.com/the-scalability-toolkit.html
Scalability testing - Further reading
1 Designing Distributed Applications with Visual Studio .NET: Scalability
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Google Search Appliance - Scalability
1 * Multiple appliances can be linked together to scale to billions of documents.
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Google Search Appliance - Scalability
1 * Physical hardware can be distributed
across multiple locations.
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Mobile banking - Scalability and reliability
1 Another challenge for the chief information officer|CIOs and chief
technical officer|CTOs of the banks is to scale-up the mobile banking
infrastructure to handle exponential growth of the customer base
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Ultra Density Optical - High capacity and scalability
1 Blue laser technology gives the 30 GB UDO more than three times the capacity of
previous generation MO (Magneto Optical) and DVD technologies. Being removable, UDO cartridges, combined with off-line
media management capabilities typical of optical storage libraries, makes UDO a much more scalable format. Rarely used data can
be removed from a library, freeing up capacity yet remaining managed and
accessible.https://store.theartofservice.com/the-scalability-toolkit.html
Scalable - Database scalability
1 A number of different approaches enable databases to grow to very
large size while supporting an ever-increasing rate of Transactions Per
Second|transactions per second. Not to be discounted, of course, is the
rapid pace of hardware advances in both the speed and capacity of mass
storage devices, as well as similar advances in CPU and networking
speed.https://store.theartofservice.com/the-scalability-toolkit.html
Scalable - Database scalability
1 One technique supported by most of the major Database management
system|database management system (DBMS) products is the
Partition (database)|partitioning of large tables, based on ranges of
values in a key field
https://store.theartofservice.com/the-scalability-toolkit.html
Scalable - Database scalability
1 Oracle RAC uses a different model to achieve scalability, based on a
shared-everything architecture that relies upon high-speed connections
between servers.
https://store.theartofservice.com/the-scalability-toolkit.html
Scalable - Performance tuning versus hardware scalability
1 It is often advised to focus system design on hardware scalability rather than on capacity
https://store.theartofservice.com/the-scalability-toolkit.html
Information and communication technologies for development - Sustainability and scalability
1 Currently, the main two perspectives coming out of this sector are to
emphasize the need for external aid to build infrastructure so that
projects can reach viability, and the need to develop and build on local
talent.
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Information and communication technologies for development - Sustainability and scalability
1 Establishing a clear and effective initial design serves as a foundation
of any development projects
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Information and communication technologies for development - Sustainability and scalability
1 Sustaining the project's scalability is a huge challenge of ICT for
development; how the target user will continue using the platform
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Information and communication technologies for development - Sustainability and scalability
1 Also, a number of developing countries have proven their skills in IT (information technology). Using
these skills to build on ICT4D projects will tap local potential and a key
indigenous partner in the growth of this sector will be gained. The
balance of trade for these nations due to imports in both computer
hardware|hardware and computer software|software might be an
additional consideration.
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Information and communication technologies for development - Sustainability and scalability
1 Different countries have variety on these strengths some are better in hardware
production, both high end and low end. There are some who are good in production of
programs and other content. ICT is a US$ 3 trillion dollar industry
(2010)http://www.deltapartnersgroup.com/ict-in-emerging-markets-a-usd-200-bln-opportunity-
that-cannot-be-ignored and is growing every year. Communication, media and IT present
opportunities for further growth and expansion.
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Xen - Scalability
1 Xen can scale to 4095 physical CPUs, 512 VCPUs per HVM guest, 256
VCPUs per PV guest, 16TB of RAM per host, and up to 1TB of RAM per HVM
guest or 512 GB of RAM per PV guest.
https://store.theartofservice.com/the-scalability-toolkit.html
Real time control protocol - Scalability in large deployments
1 In large-scale applications, such as in Internet Protocol Television (IPTV),
very long delays (minutes to hours) between RTCP reports may occur, because of the RTCP bandwidth control mechanism required to
control congestion (see #Protocol functions)
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Real time control protocol - Scalability in large deployments
1 [http://www.academypublisher.com/jnw/vol03/no03/jnw03030110.pdf Realtime control protocol and its
improvements for Internet Protocol Television]
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Software asset management - Issues with scalability
1 An example of issues faced when scaling up discovery tools is with
Microsoft's System Centre Configuration Manager (SCCM).
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Software asset management - Issues with scalability
1 Using metering rules to monitor software deployment and usage across a small
estate is relatively easy and reliable given the total number of unique executables
(.exe files) and the number of instances of each executable. If you try turning on
metering rules for every packaged application and every executable in a large
estate the volume of data generated quickly becomes unmanageable and expensive to
maintain.https://store.theartofservice.com/the-scalability-toolkit.html
Freenet - Scalability
1 As of now, the scalability of freenet has yet to be tested.
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Computer icon - Size and scalability
1 The standard icon is generally the size of an adult thumb, enabling both easy visual recognition and use in a
touchscreen device
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Nutch - Scalability
1 IBM Research studied the performance[http://www.cecs.uci.edu/~papers/ipdps07/pdfs/SMTPS-201-paper-1.pdf Scalability of the Nutch search engine] of Nutch/Lucene as part of its Commercial Scale Out
(CSO) project.[http://weather.ou.edu/~apw/
projects/cso/prov_paper.pdf Base Operating System Provisioning and
Bringup for a Commercial Supercomputer] Their findings were that a Horizontal scaling|scale-out
system, such as Nutch/Lucene, could achieve a performance level on a
cluster of blades that was not achievable on any Scalability#Scale
vertically (scale up)|scale-up computer such as the Power5.
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Nutch - Scalability
1 The ClueWeb09 dataset (used in e.g. Text Retrieval Conference|TREC) was
gathered using Nutch, with an average speed of 755.31 documents
per second.[http://boston.lti.cs.cmu.edu/
crawler/crawlerstats.html The Sapphire Web Crawler - Crawl
Statistics]. Boston.lti.cs.cmu.edu (2008-10-01). Retrieved on 2013-07-
21.https://store.theartofservice.com/the-scalability-toolkit.html
BGP - Internal BGP scalability
1 An autonomous system with internal BGP (iBGP) must have all of its iBGP
peers connect to each other in a Complete graph|full mesh (where
everyone speaks to everyone directly). This full-mesh configuration requires that each router maintain a
session to every other router. In large networks, this number of sessions
may degrade performance of routers, due to either a lack of memory, or
too much CPU process requirements.
https://store.theartofservice.com/the-scalability-toolkit.html
BGP - Internal BGP scalability
1 Route reflectors[http://www.ietf.org/rfc/rfc4
456.txt BGP Route Reflection: An Alternative to Full Mesh Internal BGP
(iBGP)], RFC 4456, T. Bates et al., April 2006 reduce the number of connections required in an AS. A
single router (or two for redundancy) can be made a route reflector: other
routers in the AS need only be configured as peers to them.
https://store.theartofservice.com/the-scalability-toolkit.html
BGP - Internal BGP scalability
1 BGP confederation|Confederations are sets of autonomous systems. In
common practice,[http://www.ietf.org/rfc/rfc50
65.txt Autonomous System Confederations for BGP], RFC 5065, P. Traina et al., February 2001 only
one of the confederation AS numbers is seen by the Internet as a whole.
Confederations are used in very large networks where a large AS can be configured to encompass smaller more manageable internal ASs.
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BGP - Internal BGP scalability
1 * route oscillation
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BGP - Internal BGP scalability
1 * increase of BGP convergence time[http://www.ietf.org/rfc/rfc4098.t
xt Terminology for Benchmarking BGP Device Convergence in the
Control Plane], RFC 4098, H. Berkowitz et al., June 2005
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NTFS - Scalability
1 In theory, the maximum NTFS volume size is 264−1 clusters
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NTFS - Scalability
1 The maximum theoretical file size on NTFS is 16exabyte|EB () minus 1 kB
or 18,446,744,073,709,550,592 bytes. With Windows 8 and Windows Server 2012, the maximum file size implemented is 256 TB minus 64 KB
or 281,474,976,645,120 bytes.
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NTFS - Scalability
1 NTFS supports a maximum cluster size of 64 kB.
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Reconfigurable Manufacturing Systems - Scalability
1 the ability to easily change production capacity by rearranging an existing manufacturing system
and/or changing the production capacity of reconfigurable stations.
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Reconfigurable Manufacturing Systems - Scalability
1 Scalability is the counterpart characteristic of convertibility. Scalability may require at the
machine level adding spindles to a machine to increase its productivity,
and at the system level changing part routing or adding machines to expand the overall system capacity (i.e., maximum possible volume) as
the marketfor the product grows.https://store.theartofservice.com/the-scalability-toolkit.html
Four square - Game scalability
1 Four square is a popular game for children and school playgrounds. It is possible to scale the game's difficulty
and supervision appropriately for different age groups and ability
levels. Schools, churches, and camps often change the size of the court, the type of ball, or aspects of the
rules to best suit the players' abilities.
https://store.theartofservice.com/the-scalability-toolkit.html
Lossy data compression - Downsampling/compressed representation scalability
1 One may wish to downsample or otherwise decrease the resolution of the represented source signal and the quantity of data used for its
compressed representation without re-encoding, as in bitrate peeling, but this functionality is not supported in all designs, as not all codecs encode
data in a form that allows less important detail to simply be
dropped.https://store.theartofservice.com/the-scalability-toolkit.html
Lossy data compression - Downsampling/compressed representation scalability
1 Some well known designs that have this capability include JPEG 2000 for still images and H.264/MPEG-4 AVC
based Scalable Video Coding for video. Such schemes have also been
standardized for older designs as well, such as JPEG images with
progressive encoding, and MPEG-2 and MPEG-4 Part 2 video, although
those prior schemes had limited success in terms of adoption into
real-world common usage.
https://store.theartofservice.com/the-scalability-toolkit.html
Lossy data compression - Downsampling/compressed representation scalability
1 Without this capacity, which is often the case in practice, to produce a
representation with lower resolution or lower fidelity than a given one,
one needs to start with the original source signal and encode, or start with a compressed representation
and then decompress and re-encode it (transcoding), though the latter tends to cause digital generation
loss.https://store.theartofservice.com/the-scalability-toolkit.html
Lossy data compression - Downsampling/compressed representation scalability
1 Another approach is to encode the original signal at several different
bitrates, and their either choose which to use (as when streaming over the internet
– as in RealNetworks' SureStream – or offering varying downloads, as at Apple's iTunes Store), or broadcast several, where
the best that is successfully received is used, as in various implementations of
hierarchical modulation
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Lossy data compression - Downsampling/compressed representation scalability
1 Some audio formats feature a combination of a lossy format and a
lossless correction which when combined reproduce the original
signal; the correction can be stripped, leaving a smaller, lossily
compressed, file. Such formats include MPEG-4 SLS (Scalable to
Lossless), WavPack, and OptimFROG DualStream.
https://store.theartofservice.com/the-scalability-toolkit.html
Extensible Host Controller Interface - Scalability
1 The xHCI architecture was designed to be highly scalable, capable of
supporting 1 to 255 USB devices and 1 to 255 root hub ports
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Extensible Host Controller Interface - Scalability
1 The xHCI maintains queue state in system memory as Endpoint Context data structures
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Extensible Host Controller Interface - Scalability
1 Also USB endpoint activity tends to be bursty. That is, at any point in time a large number of endpoints
may be ready to move data, however only a subset are actively moving data. For instance, the interrupt IN
endpoint of a mouse may not transfer data for hours if the user is away from their desk. xHCI vendor
specific algorithms could detect this condition and make that endpoint a
candidate for paging out if other endpoints become busy.
https://store.theartofservice.com/the-scalability-toolkit.html
Extensible Host Controller Interface - Scalability
1 * The xHCI architecture allows large maximum values for the number of
USB devices, ports, interrupt vectors, etc. supported, however an
implementation only needs to define the number necessary to meet its
marketing requirements. For instance, a vendor could choose to
limit the number of USB devices that it supported for a tablet xHCI
implementation to 16 devices.https://store.theartofservice.com/the-scalability-toolkit.html
Extensible Host Controller Interface - Scalability
1 * A vendor can further take advantage of xHCI architectural features to scale its internal
resources to match its target usage models. For instance, if through usability testing a vendor determines that 95% of tablet users will never connect more than 4 USB devices, and each USB device typically defines 4 endpoints (or less), then internal caching for 16 Endpoint
Contexts will ensure that under normal conditions there will be no system memory
activity due to Endpoint Context paging.
https://store.theartofservice.com/the-scalability-toolkit.html
Network on a chip - Parallelism and scalability
1 Therefore, as the complexity of Very-large-scale integration|integrated
systems keeps growing, a NoC provides enhanced performance
(such as throughput) and scalability in comparison with previous
communication architectures (e.g., dedicated point-to-point signal wires,
shared Computer bus|buses, or segmented Computer bus|buses with
bridges)https://store.theartofservice.com/the-scalability-toolkit.html
ICT for Development - Sustainability and scalability
1 Different countries have variety on these strengths some are better in hardware
production, both high end and low end. There are some who are good in production of
programs and other content. ICT is a US$3 trillion industry
(2010)http://www.deltapartnersgroup.com/ict-in-emerging-markets-a-usd-200-bln-opportunity-
that-cannot-be-ignored and is growing every year. Communication, media and IT present
opportunities for further growth and expansion.
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Publish–subscribe - Scalability
1 However, in certain types of tightly coupled, high-volume enterprise
environments, as systems scale up to become data centers with thousands
of servers sharing the pub/sub infrastructure, current vendor
systems often lose this benefit; scalability for pub/sub products
under high load in these contexts is a research challenge.
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Publish–subscribe - Scalability
1 : Outside of the enterprise environment, on the other hand, the pub/sub paradigm has proven its scalability to volumes far beyond those of a
single data centre, providing Internet-wide distributed messaging through web syndication
protocols such as RSS and Atom (standard). These syndication protocols accept higher latency and lack of delivery guarantees in
exchange for the ability for even a low-end web server to syndicate messages to (potentially)
millions of separate subscriber nodes.
https://store.theartofservice.com/the-scalability-toolkit.html
Service-oriented architecture implementation framework - Fault tolerance, reliability and scalability
1 A SOAIF should be able to offer an extremely high degree of reliability. The platform should support a broad
range of processes that span an increasing number of applications,
corporations, and partners. To eliminate single points of failure and
to maximize performance, a fully distributed architecture becomes
essential. https://store.theartofservice.com/the-scalability-toolkit.html
Service-oriented architecture implementation framework - Fault tolerance, scalability and reliability
1 Several modern ESBs implement a symmetric, distributed architecture
in which peer-messaging servers run on multiple nodes of an enterprise
network, providing a highly scalable, reliable distributed messaging platform with no single point of
failure
https://store.theartofservice.com/the-scalability-toolkit.html
Service-oriented architecture implementation framework - Fault tolerance, scalability and reliability
1 Ensuring that data flowing between services does not always have to
traverse a central point in the network optimizes peer-to-peer
network performance
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Vowpal Wabbit - Scalability
1 Vowpal wabbit has been used to learn a tera-feature (1012) data-set
on 1000 nodes in one hour.http://arxiv.org/abs/1110.4198
Its scalability is aided by several factors:
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Vowpal Wabbit - Scalability
1 * Out-of-core online learning: no need to load
all data into memory
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Vowpal Wabbit - Scalability
1 * The Feature hashing|hashing trick: feature identities are converted to a weight index via a hash (uses 32-bit
MurmurHash3)
https://store.theartofservice.com/the-scalability-toolkit.html
Vowpal Wabbit - Scalability
1 * Exploiting multi-core CPUs: parsing of input and learning are done in separate threads.
https://store.theartofservice.com/the-scalability-toolkit.html
Trust metric - Scalability
1 The growing size of networks of trust make scalability another desired
property, meaning that it is computationally feasible to calculate
the metric for large networks. Scalability usually puts two requirements of the metric:
https://store.theartofservice.com/the-scalability-toolkit.html
Trust metric - Scalability
1 * The elementary operation (e.g. fusion or discount) is computationally
feasible, e.g. that relationships between context of trust can be
quickly established.
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Trust metric - Scalability
1 * The number of elementary operations scale slowly with the growth of the network.
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Construction field computing - Scalability and continual change
1 Technologies will evolve and the user will be facing new challenges with each change. It is usually wiser to
adopt a small system that works and then later add features. This gradual
adoption reduces anxiety and increases acceptance and use. This
work by [http://www.usm.main.edu/com/linda
p~1.htm Linda V. Orr] discusses methods to reduce anxiety for new
computer users.
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Sphinx (search engine) - Performance and scalability
1 * Indexing speed of up to 10-15 MB/sec per core and HDD.
https://store.theartofservice.com/the-scalability-toolkit.html
Sphinx (search engine) - Performance and scalability
1 * Searching speed of over 500 queries/sec against 1,000,000
document/1.2 GB collection using a 2-core desktop system with 2 GB of
RAM.
https://store.theartofservice.com/the-scalability-toolkit.html
Sphinx (search engine) - Performance and scalability
1 * The biggest known installation using Sphinx, Boardreader.com, indexes 16 billion
documents.
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Sphinx (search engine) - Performance and scalability
1 * The busiest known installation, Craigslist, is rumored to serve over
250,000,000 queries/day. or 50 billion page views/month
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